Reporting from Dunwoody, Ga. —
For more than half a century, biographers have treated Franklin Delano Roosevelt with Rushmore-like reverence, celebrating the nation's 32nd president as a colossus who eased the agony of the Great Depression and saved democracy from Nazi Germany.

Which never sat right with historian Burton Folsom Jr.

Growing up in Nebraska, Folsom remembers, his dad, a savings and loan executive, griped about high taxes and Roosevelt's voracious ambition. FDR was dead, but his legacy — deficit spending, an activist federal government, an expansive social safety net — lived on.

About 15 years ago, Folsom read another of those historical surveys, this one placing Roosevelt on par with Abraham Lincoln and George Washington. "As a matter of my professional integrity," Folsom said, "I had to respond."

The result was "New Deal or Raw Deal?," a scathing 300-page counter-narrative that has made Folsom a conservative hero and placed him squarely in the midst of a roiling debate over America's past, the nature of history and, some say, its manipulation for political ends....